摘要:
A magnetic resonance (MR) surgery system facilitates surgery with a focussed ultrasound transducer that selectively destroys tissue in a region within a subject. The focussed energy transducer dissipates energy at a focal point within the region of tissue to be destroyed. A non-magnetic positioning device having a vertical dimension small enough to fit easily within the bore of an MR magnet moves an energy transducer in a limited vertical space. The positioning device employs a plurality of hydraulic positioners and an inclined plane to position the ultrasound focal point under the control of an operator. An MR imaging system employing a temperature sensitive pulse sequence creates an image of the tissue and the region being heated to allow the operator to adjust the position of the ultrasonic transducer so as to direct ultrasonic energy to the appropriate location.
摘要:
A magnetic resonance surgery system facilitates performance of surgery with a focussed ultrasound transducer that selectively destroys tissue in a region within a subject. The focussed ultrasound transducer dissipates ultrasonic energy at a focal point within the region of tissue to be destroyed. A number of hydraulic positioners position the focal point under the control of a surgeon. A magnetic resonance imaging system employing a temperature sensitive pulse sequence creates an image of the tissue and the region being heated to allow the surgeon to adjust the position of the ultrasonic transducer so as to direct ultrasonic energy to the appropriate location.
摘要:
A method for magnetic resonance imaging includes applying a first two echo gradient echo sequence to a tissue region, the first two echo sequence generating a first echo and a subsequent second echo. A second two echo gradient echo sequence is applied after heating the tissue region, the second two echo sequence generating a third echo and a subsequent fourth echo. A magnitude difference between the third echo and the first echo is measured and correlated to a temperature shift for fat tissue, and a phase difference between the fourth echo and the second echo is measured and correlated to a temperature shift for water-based tissue. A thermal image is generated of the tissue region based upon the temperature shift for both fat and water-based tissue.
摘要:
A manually positioned focussed energy transducer system facilitates medical procedures by allowing a physician to manually position the focal point of the focussed energy transducer to a selected tissue. The focal point of the focussed energy transducer is the location which tissue is destroyed when the energy transducer is activated. A tracking device tracks the position and orientation of the ultrasound transducer. An MR imaging system creates an image of internal structures of the patient near the location of the energy transducer. A superposition device receives the position and orientation of the ultrasound transducer from the tracking device and superimposes a symbol on the image corresponding to the position of the energy transducer relative to the patient. This allows the physician to adjust the position of the energy transducer to the appropriate location without the need for energizing the energy transducer.
摘要:
An automatically positioned focussed energy transducer system facilitates medical procedures by allowing a physician to interactively view the position the focal point of a focussed energy transducer superimposed upon a medical image and computer generated model of internal structures of a patient. A tracking device tracks the position and orientation of the ultrasound transducer. A medical imaging system creates an image of internal structures of the patient near the location of the energy transducer. A general purpose computer either receives a model of internal structures constructed in advance, or employs a medical imaging device to create the model. The general purpose computer displays selected surfaces of the model in an orientation and view which coincides with the medical image acquired. A superposition device receives the position and orientation of the ultrasound transducer from the tracking device and superimposes a symbol on the images corresponding to the position of the energy transducer relative to the patient. The physician then selects an internal structure to be destroyed which the general purpose computer determines the locations which the focal point must scan in order to destroy the structure. An actuator, coupled to the general purpose computer causes the focal point of the energy transducer to scan these locations which the physician adjusts the intensity of energy provided to the focal point by an input device.
摘要:
A system wirelessly supplies electrical power to an RF coil and an analog-to-digital converter (ADC) for an MRI system. The system supplies power to at least operate the RF coil and ADC without the use of a battery and without use of a wired connection external to the bore of the magnet.
摘要:
A circuit for amplifying signals received by the receive coil of a magnetic resonance (MR) system includes a preamplifier employing an active circuit device, such as a GaAs-MESFET or HEMT. The preamplifier is located proximate to the receive coil in order to maintain as high a signal-to-noise ratio as possible for the preamplifier output signals. A capacitance is coupled to the receive coil to form an input impedance matching network for the input of the preamplifier. The preamplifier output is coupled through a fiber optic cable to remotely located MR signal processing electronics, which further processes signals received by the MR receive coil and amplified by the preamplifier.
摘要:
A system wirelessly supplies electrical power to an RF coil and an analog-to-digital converter (ADC) for an MRI system. The system supplies power to at least operate the RF coil and ADC without the use of a battery and without use of a wired connection external to the bore of the magnet.